n, m, t = map(int, input().split())
M = [[0 for _ in range(n)] for _ in range(n)]
for _ in range(m):
    a, b = map(int, input().split())
    M[a][b] = 1
    M[b][a] = 1
mod = 998244353

def matmul(A, B):
    Ah, Bh, Bw = len(A), len(B), len(B[0])
    C = [[0 for _ in range(Bw)] for _ in range(Ah)]
    for i in range(Ah):
        for j in range(Bw):
            for k in range(Bh):
                C[i][j] += A[i][k] * B[k][j]
                C[i][j] %= mod
    return C

# Mのk乗を効率的に計算する
def doubling(M, k):
    k -= 1
    Mc = M.copy()
    while k > 0:
        if k & 1 == 1:
            Mc = matmul(Mc, M)
        M = matmul(M, M) # Mの(2のi乗)の乗 を計算する
        k >>= 1
    return Mc

Mt = doubling(M, t)
print(Mt[0][0])